Line 2 is the C include file for R-GMA. It must be included
to make any use of the provided R-GMA C library.

Line 4 is the name of the virtual database.

Lines 5--6 is the create table statement defining the column names and
types.

Line 7 is the authorization rule in the form
predicate:credentials:action. This can be a list of rules.

Line 9 defines a pointer to an RGMAException. Exceptions are handled uniformly
by the API. The last arument for all calls capable of failing is a pointer to a
pointer to an RGMAException.  It is essential that after each call a check is made. 

Line 10 contacts the schema and adds the table definition.

Line 11 checks to see if an RGMAException object has been created.

Line 12 report the error

Line 13 frees the exception object. This must be done each time an
RGMAException object is created by a failed call.

\input{alterTable.tex}

\subsection {Drop Table}
\label{sec:dropTable}
In order to drop a table replace line 10 from the create table example
with:
\begin{verbatim}
RGMASchema_dropTable(vdb, "userTable", &exception);
\end{verbatim}
This will remove the table definition from the schema. Within a few
minutes any producer and consumer resources still using the table will
be destroyed.